1. Field of the Invention
The present invention relates generally to a blasting apparatus and method for forming horizontal underground cavities to mine underground water, hot spring water, petroleum, natural gas, or the like, and more particularly to a blasting apparatus and method for forming horizontal underground cavities, which is capable of generating directional, continuous and concentrated explosive power by positioning and exploding the blasting apparatus at a position where fluid discharges or will discharge, thereby forming horizontal underground cavities by creating conical openings and enlarging fluid discharge passages.
2. Description of the Prior Art
While underground water, hot spring water, petroleum and gas flows out of a fluid layer such as an aquifer, an oil layer or a gas layer for a long time, detritus such as rubble, clay and/or dregs is accumulated in a portion of a fluid discharge passage through which the fluid discharges, so the amount of fluid discharged through the fluid discharge passage is decreased or, what is worse, the fluid discharge is fully blocked.
Accordingly, in order to increase the amount of fluid flowing out of a fluid layer, such as an aquifer, an oil layer or a gas layer, the following two prior arts have been proposed. A first prior art is to drill a new pit so as to mine fluid. A second prior art is to situate and explode an explosive at a position near a fluid discharge passage so as to open the partially or fully blocked fluid discharge passage by the explosive power of the explosive.
However, for the first prior art, the costs of a pit drilling operation and the costs of the removal and reinstallation of old facilities are additionally required, so it is not desirable from an economic point of view. For the second prior art, the explosive power of the explosive is scattered, so the explosive power cannot be concentrated to be sufficient to form horizontal underground cavities and may collapse the wall of the vertical pit H.
In order to open the existing fluid discharge passages, there has been utilized a blast method, in which an explosive 1 provided with a delayed detonator 2 is connected by an explosive tie 4 to a ring 5 connected to a hoisting chain 6, lowered to a position in a vertical pit H beside the existing fluid discharge passages P, and exploded at the position, as shown in FIGS. 1a to 1c. 
Such a type of explosion is conducted while an explosive is exposed to the outside, like an explosion in a hole, water or air. Hereinafter, this type of explosion is referred to as xe2x80x9can open-air type explosionxe2x80x9d.
In the open-air type explosion, since the explosive is exploded while being suspended in the vertical pit H, the explosive power of the explosive, as illustrated in FIG. 1b, is scattered over the vertical pit H. As a result, the loss of the explosive power is great and the explosive power is not concentrated, so the explosive power is not exerted on the desired area of the wall of the vertical pit H, thereby creating an incorrect blasting result.
Additionally, as illustrated in FIG. 1c, in the case of an explosion in a vertical hole, the range of the explosion is excessively wide, so great pressure is exerted upon the large area of the wall of the vertical hole. Accordingly, the wall of the vertical hole is damaged or broken, so the wall of the vertical hole is deformed or completely collapsed. As a result, the vertical hole becomes useless and an outflow passage is not newly created or not opened. That is, the conventional blasting technique is not desirable.
That is, in the open-air type explosion, since the explosive is positioned and exploded in the vertical pit H, the explosive power of the explosive is scattered through the open upper and lower portions of the vertical pit H, resulting in the loss of the explosive power and, therefore, the hindrance of the concentration of the explosive power.
For the opening of a blocked fluid discharge passage, the explosive power of the explosive should be exerted on the blocked portion of the fluid discharge passage. However, since the explosive power of the explosive is scattered, the explosive power cannot reach the blocked portion of the fluid discharge passage to open the blocked fluid discharge passage and, rather, collapses or damages the wall of the vertical pit H, thereby hindering the effective blasting of the horizontal cavities.
The conventional blasting operation is restricted to one time blasting in which the blasting apparatus is inserted into and exploded in the vertical pit H. In particular, since underground water in the vertical pit H serves as an obstacle, the blasting effect of the explosive is decreased due to the pressure of underground water, and the lowering speed of the explosive into the vertical pit is reduced due to the buoyancy of the underground water, thereby decreasing the efficiency of the blasting operation.
In addition, the instability of an explosion, such as a misexplosion, a half explosion or the like, is created due to water pressure, the explosion effect of a shaped explosive cannot be utilized because of the open-air type explosion, and the explosive is difficult to handle safely due to problems such as the contact of the explosive with the wall of the vertical pit H.
The inventor of the present invention proposes xe2x80x9ca closed type explosionxe2x80x9d that is capable of obtaining directional, concentrated and continuous explosive power. In the closed type explosion, an explosive is exploded in a sealed explosion space that is separated from the surroundings.
To this end, there is provided a blasting apparatus for forming horizontal underground cavities. In the blasting apparatus of the present invention, a loading chamber is horizontally formed through the center portion of a metallic body and a shaped explosive and a delayed detonator are loaded in the loading chamber so as to allow the explosive power of the shaped explosive to be concentrated and exerted in a horizontal direction.
Additionally, there is provided a blasting method using the blasting apparatus for forming horizontal underground cavities, in which the blasting apparatus is situated and exploded one or many times at a position where fluid discharges or will discharge, thereby forming conical openings and enlarging fluid discharge passages.
Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a blasting apparatus for forming horizontal underground cavities and method using the same, which is capable of directing explosive power in a horizontal direction by exploding a shaped explosive in a restricted, horizontal loading chamber, so the explosive power of the shaped explosive is concentrated in the direction perpendicular to the direction of a vertical pit and the explosive power is continued, thereby forming horizontal underground cavities without the collapse of the wall of the vertical pit by exerting explosive power on the desired area of the wall of the vertical pit.
Another object of the present invention is to provide a blasting apparatus for forming horizontal underground cavities and method using the same, which is capable of enlarging a fluid discharge passage and reopening a blocked fluid discharge passage without requiring a new pit drilling operation to regenerate an existing pit when the amount of fluid is reduced or a fluid discharge passage is blocked while fluid is mined from an underground water pit, a hot spring pit, a natural gas pit or a petroleum pit, thereby saving the costs of a new pit drilling operation and the costs of the removal and reinstallation of facilities and improving the economic efficiency of a underground cavity blasting operation.
A further object of the present invention is to provide a blasting apparatus for forming horizontal underground cavities and method using the same, which is capable of generating directional explosive power, being repeatedly exploded and being circumferentially exploded when an underground water pit, a hot spring pit, a natural gas pit or a petroleum pit is developed, so the probability of success of an underground cavity forming operation is maximized.
A still further object of the present invention is to provide a blasting apparatus for forming horizontal underground cavities and method using the same, which obviates the need for excessive pit drilling operations that are carried out to mine underground water, petroleum or gas, so underground pollution through the drilled pits can be prevented, thereby contributing to environmental conservation.
In order to accomplish the above object, the present invention provides a blasting apparatus for forming horizontal underground cavities, comprising: a metallic body horizontally formed through a center portion of a loading chamber; a delayed detonator and a shaped explosive loaded in the loading chamber of the body; and a connecting ring formed on the body for connecting the body to a hoisting rope.
The blasting apparatus may further comprise two pipe-shaped gaps formed in the body around the loading chamber, the two pipe-shaped gaps being coaxial with the loading chamber and each having a diameter larger than the loading chamber; two delayed detonators and two propulsive explosives loaded in the pipe-shaped gaps; and two plastic sealing pipes for stopping up the pipe-shaped gaps after the delayed detonators and the propulsive explosives are loaded in the pipe-shaped gaps.
The body may be formed in the shape of an egg so as to reduce friction between the body and fluid filling a vertical pit while the body is lowered through the vertical pit.
The body may have a width in the range of 80 to 90% of the diameter of the vertical pit.
The apparatus may further comprise a through hole for a detonator lead, the through hole being extended from the upper surface of the body to the center portion of the loading chamber.
The apparatus may further comprise one or more through holes for one or more detonator leads, the through holes being extended from the upper surface of the body to the center portion of the pipe-shaped gaps.
The body may have a weight in the range of 50 to 500 kg.
The shaped explosive may be provided at both ends with cone-shaped recesses.
The apparatus may further comprise two funnel-shaped lines, the liners being attached to the cone-shaped recesses, respectively.
The shaped explosive may have the amount of loading in the range of 0.1 to 1 kg.
The apparatus may further comprise two covers, the covers being attached to stepped portions of the entrances of the loading chamber loaded with the shaped explosive.
The connecting chain may comprise a plurality of rings to prevent the connecting chain from being twisted.
In addition, the present invention provides a blasting apparatus assembly for forming horizontal cavities, comprising a plurality of metallic bodies each horizontally provided with a loading chamber; a plurality of delayed detonators and a plurality of explosives loaded in the loading chambers of the bodies; and a plurality of connecting chains each connecting one body to another.
The blasting apparatus may each further comprise two pipe-shaped gaps formed in the body around the loading chamber, the two pipe-shaped gaps being coaxial with the loading chamber and each having a diameter larger than the loading chamber; two delayed detonators and two propulsive explosives loaded in the pipe-shaped gaps; and two plastic sealing pipes for stopping up the pipe-shaped gaps after the delayed detonators and the propulsive explosives are loaded in the pipe-shaped gaps.
The blasting apparatuses connected to one another by the connecting chains may have the loading chambers with each of loading chambers of one blasting assembly arranged in the same direction as a corresponding loading chamber of another blasting assembly.
The blasting apparatuses connected to one another by the connecting chains may have the loading chambers with each of loading chambers of one blasting apparatus arranged to be perpendicular to a corresponding loading chamber of a neighboring blasting apparatus.
In addition, the present invention provides a blasting method for forming horizontal cavities, comprising the steps of loading a detonator lead, a delayed detonator and a shaped explosive in a loading chamber horizontally formed through a center portion of a body of a blasting apparatus; suspending the blasting apparatus over a vertical pit by operating a hoisting device after a connecting ring of a body of the blasting apparatus is connected to a hoisting rope by a connecting chain; lowering the blasting apparatus suspended by the hoisting rope to an entrance of a vertical pit, and connecting a detonator lead drawn out of the body to a leading wire wound around a take-up device positioned on a support surface just before the blasting apparatus enters the vertical pit; lowering the blasting apparatus and the leading wire connected to the detonator lead drawn out of the body into the vertical pit at a position where fluid discharges; detonating the shaped explosive loaded in the blasting apparatus positioned at the position where fluid discharges or will discharge; and retrieving the body of the blasting apparatus by lifting the body using the hoisting device.
The explosive detonating step may comprise the steps of firstly detonating delayed detonators and propulsive explosives loaded in two pipe-shaped gaps, which are coaxial with the loading chamber and have a diameter larger than the loading chamber, so as to bring two sealing pipes into contact a with the wall of the vertical pit and seal a detonating space from the outside; and secondly detonating the shaped explosive loaded in the loading chamber.
The blasting apparatuses may have the loading chambers with each of loading chambers of one blasting assembly arranged in the same direction as a corresponding loading chamber of another blasting assembly, and the blasting apparatuses may be sequentially lowered to and repeatedly exploded at an explosion position to repeatedly blast the position.
The blasting apparatuses may have the loading chambers with each of loading chambers of one blasting apparatus arranged to be perpendicular to a corresponding loading chamber of a neighboring blasting apparatus, and the blasting apparatuses may be sequentially lowered to and repeatedly exploded at an explosion position to circumferentially blast horizontal cavities.
The detonating step may be performed by a remote controller.